Simulation And Analysis Of Fine Weather Fields In Chengdu Based On Urban Canopy Model

In recent years,Chengdu has experienced rapid urban development.In addition to facilitating people's lives,it has also brought about various problems.The impact of urban development on Chengdu's climate is the key and difficult point of Chengdu's development planning.In this paper,the numerical model is used to simulate the meteorological field in Chengdu.In order to simulate the urban meteorology more accurately,this paper replaces the underlying surface used in the simulation with the finely classified underlying surface,and couples the urban canopy model into the numerical model.Improvement,using the monitoring data to verify the simulation results,and finally get reasonable simulation results,and theoretical analysis of the results.The conclusions are as follows:(1)For the wind speed simulation results,the addition of the urban canopy model optimizes the simulation results of urban wind direction and wind speed.The simulation results of the single-layer urban canopy model are slightly better than the multi-layer urban canopy model.(2)For the temperature simulation results,the urban canopy model can better simulate the temperature change of static and stable weather.Among them,the multi-layer urban canopy mode is calculated many times due to the transfer of heat and energy.The simulation results are better than the single-layer urban canopy model.(3)For the humidity simulation results,the urban canopy model can simulate the state of high humidity under static and stable weather.The simulation results of the multi-story urban canopy model are better than the single-layer urban canopy model.(4)The WRF model with fine classification of the underlying surface has a good improvement on the simulation results of wind speed.Although the wind speed is still too large,the overall simulation results are better than the WRF default underlying surface and local climate division.The simulation results were passed and a significance test was passed.The simulation results of the multi-story urban canopy model are better than the single-layer urban canopy model.(5)The simulation results of humidity and temperature using WRF mode with finely classified underlying surface are better than the simulation results of WRFdefault underlying surface and local climate zoning,and pass the significance test,so the simulation results can be used for meteorology.Field analysis.(6)By increasing the surface roughness of the underlying surface of the city,the WRF model can simulate the characteristics of urban wind field discontinuity and randomness.(7)The WRF model can not simulate the air pollution situation,but it can still simulate the cold island effect and heat island effect of polluted or non-polluting days.